crypto: ccp: Skip SEV and SNP INIT for kdump boot

Since SEV or SNP may already be initialized in the previous kernel,
attempting to initialize them again in the kdump kernel can result
in SNP initialization failures, which in turn lead to IOMMU
initialization failures. Moreover, SNP/SEV guests are not run under a
kdump kernel, so there is no need to initialize SEV or SNP during
kdump boot.

Skip SNP and SEV INIT if doing kdump boot.

Tested-by: Sairaj Kodilkar <[email protected]>
Signed-off-by: Ashish Kalra <[email protected]>
Link: https://lore.kernel.org/r/d884eff5f6180d8b8c6698a6168988118cf9cba1.1756157913.git.ashish.kalra@amd.com
Signed-off-by: Joerg Roedel <[email protected]>

Author: ashkalra

drivers/crypto/ccp/sev-dev.c

@@ -28,6 +28,7 @@
 #include <linux/fs_struct.h>
 #include <linux/psp.h>
 #include <linux/amd-iommu.h>
+#include <linux/crash_dump.h>
 
 #include <asm/smp.h>
 #include <asm/cacheflush.h>
@@ -1345,6 +1346,15 @@ static int _sev_platform_init_locked(struct sev_platform_init_args *args)
 	if (!psp_master || !psp_master->sev_data)
 		return -ENODEV;
 
+	/*
+	 * Skip SNP/SEV initialization under a kdump kernel as SEV/SNP
+	 * may already be initialized in the previous kernel. Since no
+	 * SNP/SEV guests are run under a kdump kernel, there is no
+	 * need to initialize SNP or SEV during kdump boot.
+	 */
+	if (is_kdump_kernel())
+		return 0;
+
 	sev = psp_master->sev_data;
 
 	if (sev->state == SEV_STATE_INIT)